greening the machine

Monday, May 29, 2006

Cobb Hill Co-Housing Devleopment

Cobb Hill CohousingHartland, VTJeff Schoellkopf Design

Integrated design consulting for a 22 unit plus Common House cohousing community. Founded by the late Donella Meadows, this community brought together an amazing group of people with a deep environmental ethic. Putting together two old Vermont farms, some of the residents raise sheep, tap a maple sugarbush, operate a CSA farm, and make cheese. Also on site is the Sustainability Institute, a think-do tank also founded by Meadows.

Features include a central high-efficiency, wood-fired boiler that supplies heat and hot water to the community through an underground district heating system; composting toilets in all the buildings; highly insulated construction (all homes are VT Energy Star rated); and healthy, non-toxic construction. Solar hot water and solar electric systems have been installed on some of the homes. Occupied 2001.

This project description was written by Marc Rosenbaum, P.E. - PO Box 194, Meriden, NH 03770 603-469-3355 who collaborated on this project.

Boilers and Space Heaters

Green Pages has information on various boilers and space heaters.

check it out.

Vacuum Tube Collectors

Glass vacuum-tube solar collectors explained

Both the Skypower HW470 Series and the Consol Series solar water heaters use an array of glass vacuum-tube collectors (also known as evacuated-tubes) to efficently convert solar energy into hot water. Evacuated-tube collectors heat water in residential applications that require higher temperatures.

Why vacuum-tube Collectors are ideal

Vacuum tube collectors perform well in both direct and diffuse solar radiation. This characteristic, combined with the fact that the vacuum minimizes heat losses to the outdoors, makes these collectors particularly useful in areas with cold, cloudy winters.
Also, because of the circular shape of the evacuated tube, sunlight is perpendicular to the absorber for most of the day. By comparison, in a flat-plate collector that is in a fixed position, the sun is only perpendicular to the collector at noon.

How vacuum-tube collectors work

In an evacuated-tube collector, sunlight enters through the outer glass tube, strikes the absorber tube, and changes to heat. The heat is transferred to the liquid flowing through the absorber tube.
The collector consists of rows of parallel transparent glass tubes, each of which contains an absorber tube (in place of the absorber plate in a flat-plate collector) covered with a selective coating.
The selective coating transforms the solar energy ino heat, and transfers it to either water (in the case of the Skypower Series) or a copper, heat conducting element (in the case of the Consol units).
Reflectors placed behind the evacuated tubes in the Consol and Skypower HW470 Series water heaters help to focus additional sunlight on the collector, for maximum effiency.

Vacuum-tube construction minimises heat loss

When evacuated tubes are manufactured, air is evacuated from the space between the two tubes, forming a vacuum. Conductive and convective heat losses are eliminated because there is no air to conduct heat or to circulate and cause convective losses. This is exactly the same principle that keeps drinks hot or cold in a Thermos Flask.

There is still a small amount of radiant heat loss, but it is far lower than for most other collector types

Vacuum Tube Collectors

Glass vacuum-tube solar collectors explained

Both the Skypower HW470 Series and the Consol Series solar water heaters use an array of glass vacuum-tube collectors (also known as evacuated-tubes) to efficently convert solar energy into hot water. Evacuated-tube collectors heat water in residential applications that require higher temperatures.

Why vacuum-tube Collectors are ideal

Vacuum tube collectors perform well in both direct and diffuse solar radiation. This characteristic, combined with the fact that the vacuum minimizes heat losses to the outdoors, makes these collectors particularly useful in areas with cold, cloudy winters.
Also, because of the circular shape of the evacuated tube, sunlight is perpendicular to the absorber for most of the day. By comparison, in a flat-plate collector that is in a fixed position, the sun is only perpendicular to the collector at noon.

How vacuum-tube collectors work

In an evacuated-tube collector, sunlight enters through the outer glass tube, strikes the absorber tube, and changes to heat. The heat is transferred to the liquid flowing through the absorber tube.
The collector consists of rows of parallel transparent glass tubes, each of which contains an absorber tube (in place of the absorber plate in a flat-plate collector) covered with a selective coating.
The selective coating transforms the solar energy ino heat, and transfers it to either water (in the case of the Skypower Series) or a copper, heat conducting element (in the case of the Consol units).
Reflectors placed behind the evacuated tubes in the Consol and Skypower HW470 Series water heaters help to focus additional sunlight on the collector, for maximum effiency.

Vacuum-tube construction minimises heat loss

When evacuated tubes are manufactured, air is evacuated from the space between the two tubes, forming a vacuum. Conductive and convective heat losses are eliminated because there is no air to conduct heat or to circulate and cause convective losses. This is exactly the same principle that keeps drinks hot or cold in a Thermos Flask.
There is still a small amount of radiant heat loss, but it is far lower than for most other collector types.

Ground Source Heat Pump

A geothermal exchange heat pump, also known as a ground source heat pump, is a heat pump that uses the Earth as either a heat source, when heating the home, or a heatsink when cooling it. All geothermal heat pumps are characerized by an external loop containing water and antifreeze (propylene glycol, denatured alcohol or methanol), and a much smaller internal loop containing a refrigerant. Both loops pass through the heat exchanger.

There are three categories of geothermal heat pumps based on the type of external loop: open loop sytem, closed loop vertical system, and closed loop horizontal system. The open loop system draws water from one well passes it through a heat exchanger in the house, then injects it into a second well. The pipe in vertical closed loop system uses a single well with the fluid in the pipe constanly recirculated to and from the well. The horizontal closed loop is placed below the frostline (1 to 2 m) underground. Whether a vertical or horizontal closed loop system the pipe is often spiral to increase the contact area per length. A typical 2,000 sq. ft. (185.8 m²) residence will require four tons (14.06 kilowatts) of heating capacity. Each ton of heating capacity requires approximately 91 m (300 ft) of vertical loop or 122 m (400 ft) of horizontal loop. Thus the typical residence will require 366 m (1200 ft) of vertical loop or 488 m (1600 ft) of horizontal loop.

The Earth below the frost line remains at a relatively constant temperatureyear round, usually between 7-21 degrees Celsius (45-70 degrees Fahrenheit) depending on geographical location. This property allows geothermal heat pumps to perform with far greater efficiency and in a far larger range of extreme temperatures than conventional air conditioners and furnaces.


Making Hot Water

Geoexchange systems can also provide all or part of a household’s hot water. This can be highly economical, especially if the home already has a geoexchange system, hence a ground loop, in place.

One economical way to obtain a portion of domestic hot water is through the addition of a desuperheater to the geoexchange unit. A desuperheater is a small, auxiliary heat exchanger that uses superheated gases from the heat pump’s compressor to heat water. This hot water then circulates through a pipe to the home’s water heater tank. In summer, when the geoexchange system is in the cooling mode, the desuperheater merely uses excess heat that would otherwise be expelled to the loop. When the geoexchange unit is running frequently, homeowners can obtain all of their hot water in this manner virtually for free. A conventional water heater meets household hot water needs in winter if the desuperheater isn’t producing enough, and in spring and fall when the geoexchange system may not be operating at all.

Because geoexchange systems heat water so efficiently, many manufacturers today are also offering triple function geoexchange systems. Triple function systems provide heating, cooling and hot water. They use a separate heat exchanger to meet all of a household’s hot water needs.

Passive Solar Homes

there is a nice power point presentation on Passive Solar Homes at: terri/powerpoint/passive_design.ppt

Sun Frost Composting Toilets

Sun Frost “Human Humus Machine” Composting Toilet

"This composting toilet is not only a great way to recycle waste products, but it is the cleanest composting toilet we’ve used. Our facility is on a city park and is heavily used, yet it never smells and requires very little maintenance. It is a great way to close the waste production to fertilization loop."–Kevin Cunningham Arcata Educational Farm Arcata, CA
“Finally, a simple composting toilet that really works! It’s easy to deal with… and produces a compost you would never guess to be human waste. It even handles urine without becoming anaerobic.”Eddie Tanner – Human Humus Machine user for 3 years
The Human Humus Machine produces high quality humus, which has the same appearance and aroma as high-quality topsoil. Heat-generating and pathogen-consuming microbes control pathogens in the finished compost.
The Human Humus Machine is available in a relatively low-cost kit form. The kit consists of all the parts necessary to convert two 55-gallon drums into a state-of-the-art composting toilet. The drums have a plastic liner to eliminate rusting. The kits are easy to assemble and can be completed in less than 2 hours. The installer would obtain the drums locally. We can also offer fully assembled units.
The Human Humus Machine is a batch-type CT. After the drum is full, the contents of the drum are allowed to sit for a number of months to complete the composting process. In non-batch type composters, newly deposited material can contaminate compost ready to be removed.

Sun Frost Home Composter

The Sun Frost Scrap Eater -

A Stylish, High-Tech ComposterCreating mineral-rich soil from your table scraps is finally convenient, clean and easy with the Sun Frost Scrap Eater - a state of the art "living machine." This composter is a highly functional piece of appropriate technology that is also stylish and fun to use.
Plants growing in the soil on the perimeter of the Scrap Eater feed directly off nutrients that you create in the composting section. This miniature ecosystem composts food scraps in a sealed compartment so you can display the Scrap Eater on a deck, porch or even an apartment patio without concern about odors, insects or animals.

Sun Frost Refrigerator

Cold Weather Passive Assist Refrigeration

If you live in a cold climate, your refrigerator is often running when the temperature outside is colder than it is in your refrigerator. A simple way of using the “coolth” from the outside to cool your refrigerator is by incorporating a heat pipe. A heat pipe is a passive device that transfers heat by evaporation and condensation. Steam heat and steam cooking vegetables are examples of heat pipes in use. Absorbed heat boils water, the steam then condenses and releases its heat while heating your house or cooking your food, the condensed water then drains back to the boiler.

A heat pipe can be used to transfer heat from a refrigerator compartment to the outside. When the temperature is colder outside than in the refrigerator, the liquid in the refrigerator boils, absorbing heat and cooling the refrigerator compartment. The refrigerant then condenses outside and runs back to the refrigerator (see diagram). The pressure in the tube changes with temperature, so the liquid always boils when the temperature is colder outside than in the refrigerator. This device acts as a one-way thermal valve, if the temperature is hotter outside than in the refrigerator heat is not transferred into the refrigerator.

Refrigerators we manufactured incorporating a heat pipe also contain an active cooling system. When the temperature outside warms and the refrigerator can no longer be passively cooled, a thermostat with a preset temperature will turn on the compressor and cool the refrigerator compartment. Installation required only drilling a _ inch hole for the heat pipe running from the refrigerator to the outside.

In the mid 1980’s we built about ten of these hybrid refrigerators. The models without a freezer compartment coupled very effectively with a solar system. Since during the winter when available sunlight is limited, the refrigerator is passively cooled and requires no energy to run. With our RF16, the freezer compartment consumes about 60% of the total energy consumed by the unit. During the winter, the heat pipe would decrease energy use by 40%. One of the passively cooled refrigerators is located at the Rocky Mountain Institute in Colorado, where winters are long and passive cooling is effective. Although these refrigerators operate effectively, sales were limited and we no longer manufacture that model.

Sun Frost refrigerators and freezers are so outstandingly energy-efficient, powering a home with solar power or other low output energy sources is both feasible and affordable. All models are available in 12 or 24 volt DC, or 110 or 220 volt AC. Even in a home using conventional utility power, energy consumption for refrigeration is typically cut by a factor of five.

Cut Off Phantom Loads

Phantom loads are things that are always on, drawing power, even when turned off. Microwave ovens, VCRs, TVs, computers, and most stereo equipment are a few of the typical household phantom loads. Each device may draw only a few watts, but for several reasons they can use up a surprisingly large portion of a power system's output. The simple solution is wall switches to control outlets wherever such specific devices will be located. This allows the client an easy way to eliminate such waste.
Ghost Loads

Ghost loads (or phantom loads) refer to anything in your home or business that is on constantly even if you think it is 'off.' Very small LED lights count, too! For example: the clock on your microwave, VCR, or stove, the red light on your TV that shows it is warmed up and ready to accept a signal from the remote and be turned on, a cell phone charger, nightlights, even electric alarm clocks. These items require electricity 24 hours per day, 365 days per year, and that adds up!

Whether it's a 1 watt per hour load from your microwave’s digital clock (that’s 24 watts every single day) or 7 watts per hour from your alarm clock (that equals 168 watts each day), these things need energy all the time. So what is the solution to these ghost loads? There are various ways to attack them.

First, your alarm clock can be battery powered (use rechargeable batteries, if possible). The TV can be plugged into a power strip that gets turned off after you are done watching TV each time and the same can hold true for the microwave. Battery chargers, such as for a drill or rechargeable batteries, can be unplugged when not in use. If you absolutely need nightlights, they are now available in liquid crystalline varieties that are blue or green colored, and take a very, very tiny fraction of energy to produce the same amount of light as nightlights with little incandescent light bulbs. Take a slow stroll through your home and see everything that is plugged in and always on. Buy some power strips for them and save money daily with conservation.

Phantom load, sometimes referred to as standby power or leaking electricity is the power consumed by any device while it is switched off.

Many of the appliances in homes today consume power when they are turned off. These include stereos, VCRs and television sets. The phantom load can be caused by miniature transformers (such as wall warts) that convert AC electricity into DC electricity. The conversion is most efficient with large power draws, such as refrigerators, and least efficient with device that require little power, such as digital clocks. Phantom load is also caused by devices that have a small LED or other indicator to show that they still have power. These displays obviously use electricity.

For any single appliance the load is never that large (the most inefficient designs draw 15-20 watts), however when factored over all of the appliances in a country like the U.S. the load can come to billions of watts. Some studies have suggested that the total phantom load caused by the United States alone would provide enough power to handle the electric needs of Vietnam, Peru, and Greece. Suggestions for reducing the phantom load include the use of a surge protector. When the surge protector is turned off, the appliance can no longer draw power from an outlet, thereby reducing phantom load.

Finding phantom loads is not always easy. "Gas" stoves that use an electric clock constitute a phantom load. Recommended methods for finding phantom loads include turning off all lights at night and look for any LEDs or other glows in the house. Any device that requires resetting after a blackout or power surge is a cause of phantom load. "Instant on" features are often an indicator of phantom load.

A simple test using a 'true power meter' or energy meter found that an all in one hi-fi unit (CD, tuner, tape deck) consumed 20W when 'off' and 60W when on but silent. Similarly, a recent microwave oven with a clock used 15W when not cooking (A similar model with a mechanical timer used no measurable power when not in use). It was found that recent models generally used more power in standby than devices from 5 years ago! An average suburban house was found to draw 300W of standby current averaged over the year.

Although not considered a true phantom load, desktop computers left on will draw around 150W continuously. A laptop generally uses less than 50W, usually around 20W average

Recessed Lighting

This Model is made by AIR-TITE, $32.
Recessed Lights

Older recessed lights can be a big source of air leakage, but sealing them can be tough. Insulation must be kept at least 3" away from the older style lights because of the heat they give off. Experts often make boxes to cover the recessed light fixtures in the attic out of fire resistant wallboard to reduce leakage. However, unless the boxes are made large enough, the lights can overheat. The boxes should allow at least 3" space on all sides of the light fixture. If loose fill insulation is installed, a metal cylinder with an open top can be used as an insulation dam to keep the insulation away from the light. However, the dam will not prevent air leakage around the light. If you are planning a remodel job, leaky, old-style recessed lights can be replaced with "IC rated" lights. These lights can be in contact with insulation, and more recent brands are air-tight. Many of the new recessed light fixtures that are sealed use CFL bulbs, a great energy-saving combination.

Heat Recovery Ventilation (HRV)

Heat recovery ventilation is a ventilation system that employs a heat exchanger between the inbound and outbound air flow to save on energy required for heating (or cooling) the room.

Heat recovery ventilators (HRV's), as the name implies, bring fresh air into a building while recovering the heat energy in the exhaust air. They are closely related to Energy Recovery Ventilators (ERV), however ERV's differ in that they also "recover" the humidity (or lack of it) in the exhaust air.

As residential buildings have become more leak free (aka tighter), the need for HRV's has become obvious. A tight building will require a source of fresh air. It does not make any sense to open the window for ventilation during cold weather, since this destroys the energy efficiency of the building. Hence, the need for an HRV.


a lot of specific product information can be found at:


Frequently Asked Questions

Who needs an HRV/ERV?

Every home (new and old) needs ventilation to bring in fresh air, to remove stale air, and provide moisture control. Effective July, 1999, new homes constructed in Minnesota will be required to have a mechanical ventilation system to supply outdoor air for the people inside the home. An HRV/ERV is one mechanical ventilation system that offers convenience, comfort and building durability. In new construction, the connections should be roughed in if, for budget reasons, you do not install the HRV/ERV during construction.

Where do I go to buy an HRV/ERV?

A good mechanical contractor is the key to success. If you are building a new house or remodeling, ask your building contractor about the mechanical ventilation options or check the yellow pages for heating and cooling contractors. A contractor experienced in ventilation should be able overcome any obstacles related to the installation. This would include balancing the system and verifying flow to all pickup points and insuring proper application, i.e., sizing, location of inlets and outlets, and zone control.

How much does it cost to install an HRV/ERV?

Costs can vary a lot depending on the type and complexity of the installation, as well as on the size and features of the HRV/ERV. For new construction, the costs would normally run from $1,000 to $2,500. It will generally cost more for a retrofit, due to the difficulty of running ductwork to the source points. Volume (or non-source point) ventilation systems can be installed at a lower cost, but may not be as effective and will require the furnace fan to run continuously.

Different Kinds of Thermal Insulation

There is a list of advantages, disadvantages and information on many of the most common thermal insulators at:

some general R-values:

Air with no external wind = R-5 (still) to R-1 (with convective currents).
Single pane glass window = R-1.
Wood chips and other loose-fill wood products = R-1.
Snow = R-1.
Straw bales = R-1.45. [17]
Double pane glass window = R-2.
Double pane glass window with low emissitivity coating = R-3.
Triple pane glass window = R-3.
Wood panels, such as sheathing = R-2.5.
Vermiculite loose-fill = R-2.13 to R-2.4.
Perlite loose-fill = R-2.7.
Rock wool loose-fill = R-2.0 to R-3.3.
Rock wool batts = R-3 to R-3.85.
Fiberglass loose-fill = R-2.2 to R-3.7.
Fiberglass rigid panel = R-2.5.
Fiberglass batts = R-2 to R-3.85.
High-density fiberglass batts = R-3.6 to R-5.
Cementitious foam = R-2 to R-3.9.
Cellulose loose-fill = R-3 to R-3.8.
Icynene spray = R-3.6.
Icynene loose-fill = R-4.
Urea-formaldehyde foam = R-4 to R-4.6.
Urea-formaldehyde panels = R-5 to R-6.
Phenolic spray foam = R-4.8 to R-7.
Phenolic rigid panel = R-4 to R-5.
Molded expanded polystyrene (EPS) = 3.7 for low-density, 4 for high-density.
Foiled-faced expanded polystyrene (EPS) = R-10 to R-27.4.
Extruded expanded polystyrene (XPS) = 3.6 to 4.7 for low-density, 5 to 5.4 for high-density.
Polystyrene spray foam = R-5.
Open-cell polyurethane spray foam = R-3.6.
Closed-cell polyurethane spray foam = R-5.5 to R-6.5.
Polyurethane rigid panel = 6 (expanded with air), 6.25 to 9 (expanded with CFC or HCFC).
Polyisocyanurate spray foam = R-4.3 to R-8.3.
Foil-faced polyisocyanurate rigid panel = R-5.8 to R-7.4.
Silica aerogel = R-10.
Foil-backed bubble pack = R-6 to R-18?
Vacuum-insulated panel = as high as R-30?

Sunday, May 28, 2006

Vapor Barriers

Generally, vapor barrier is a term often used when discussing humidity (or vapor pressure) where vapor (e.g. water vapor) is prevented from moving between discrete spaces or volumes.
For example, the roof, walls, and windows in a house keep the air inside and outside the house separate. Any gaps (e.g. open windows or open doors, or gaps around these) will not be a barrier to vapor. Usually, if air can pass, so can vapor.

More specifically, a vapor barrier is a material that is impermeable to vapor. They are usually made out of plastic, such as polyethylene. Whatever material is used, it must have a permeability rating of 1 or lower. Vapor barriers are installed on the interior side of a wall. They protect the wall and insulation from being damaged by condensation. The air inside a structure is warm and warm air can hold more moisture than cold air. When warm air hits a colder surface, like the inside of a wall, it may release the water it is carrying as condensation. This can cause rotting or mold growth.

Another definition of vapor barrier, worded slightly differently:

A vapor barrier is any material, usually a plastic or foil sheet, that resists passage of both air and moisture through walls, ceilings, and floors. They help prevent interior moisture from penetrating into and condensing in unheated attics, basements, crawlspaces, and wall cavities. This is especially important in well-insulated homes, where there is often a great difference in temperature between the air in conditioned space and the air in unconditioned space. The vapor barrier is placed in between the insulation and the conditioned space, usually stapled to the studs.

A vapor barrier must be continuous to work properly. There should be no tears, and you should seal electrical receptacles and switches, windows, and locations where walls meet ceilings and floors. Some people think that vapor barriers are inherently flawed solutions for preventing moisture from entering wall cavities, because you poke them with hundreds of holes when you staple them to the framing studs, and you poke them with hundreds more holes when you install the drywall. Furthermore, there is no way to make sure that a contractor installed the vapor barrier properly once the drywall is installed. Using closed-cell spray foam between framing and closed-cell rigid foam over sheathing is more expensive than fiberglass and cellulose, but closed-cell foam resists air infiltration, is virtually impermeable to water, and makes a vapor barrier unnecessary (since the wall cavities are kept warm).

Vapor barriers have permeability ratings of 1.0 or lower, indicating their resistance to the passage of air (including moisture). Do not use asphalt felt paper as a vapor barrier. Asphalt felt paper has a permeability rating of approximately 1.0, so it doesn’t do a good job of trapping water. There are several alternatives that are far superior.

Marc Rosenbaum

On May 20th I attended Marc Rosenbaum's eight hour seminar entitled: Towards Zero Energy Homes. Marc seemed to be a practical, wise and excitable man. His method of building and his dynamic conceptual understanding of energy "eco-systems" comes from years of trial and error. During the eight hours of his open seminar lecture marc explored his worst mistakes and shining victories. Interwoven between quips about his wife being from minnesota and his hatred for most german enginering was pragmatic building advice and suggestions to the croud of architechts, builders, teachers and students. He spoke in a way that could be understood by both engineers and architechs alike and would be very helpful in answering specific questions that you might have about building green. Marc is a great resource for the Green Movement and I felt honored to be able to meet him in person.

An Overview of Background and Experience

Marc Rosenbaum, P.E. uses an integrated systems design approach to help people create buildings and communities which connect us to the natural world, and support both personal and planetary health. He brings this vision, experience and commitment to a collaborative design process, with the goal of profoundly understanding the interconnections between people, place, and systems that generate the best solution for each unique project. Design practiced at its highest level goes beyond efficiency and conservation to create places that regenerate and nurture the natural world and all of its inhabitants.

Energysmiths was founded in 1979 on the principle that sustainable communities can only be based on renewable resources. Marc has focused on integrating renewable energy systems, daylighting, high performance envelope design, health-sustaining mechanical systems, food production and storage, ecological waste systems, efficient electrical and water systems, and benign, resource-efficient materials selection into his projects. Having realized that the barriers to high performance buildings and communities are neither technical nor economic, his work scope has expanded to assist clients design the process that is necessary to create these high performance projects.

Projects of his have won awards from the Northeast Sustainable Energy Association (NESEA – four times a winner), ASHRAE (twice a winner), and the Energy Efficient Building Association (EEBA). His Hanover House project was one of the American Institute of Architects (AIA) Earth Day 2000 Top Ten. The French Wing for the Society for the Protection of NH Forests was recently awarded a Gold LEED certification, the first LEED certified project in New England.

In his practice of sustainable design consulting, he has worked for institutional clients such as MIT, Vermont Law School, Yale, Dartmouth College, White Mountain School, and Middlebury College; non-profit clients such as the Society for the Protection of NH Forests and the Woods Hole Research Center; commercial clients such as Stonyfield Farm, Inc., Tom’s of Maine, and the Hanover Consumer Co-op; cohousing groups such as Pioneer Valley, Pine Street, Island Cohousing, New View, Cobb Hill, and Alchemy Farm; and with many architects including William McDonough Architects, Tsoi/Kobus, Solar Design Associates, Bruner Cott Associates, Moore Ruble Yudell, and Payette Associates, in association with BNIM Architects.

He has been published in ASHRAE Journal, Fine Homebuilding, Northeast Sun, Solar Today, Journal of Light Construction, and Northwest Builder, and is a member of the Advisory Board of Environmental Building News.He is a frequent speaker on sustainable design and has been a featured presenter at many conferences, with audiences that include architects, engineers, construction professionals, facilities managers, planners, educators, utility professionals, and those working in the public sector.An experienced and enthusiastic teacher, he has trained thousands of professionals and especially enjoys working with students. He holds BS and MS degrees from MIT, where he studied mechanical engineering. He is a licensed engineer in NH, VT, MA, and ME, and is a LEED Accredited Professional, certified by the U.S Green

Building Council.energysmithsP.O. Box 194 Meriden, NH 03770603-469-3355; 603-469-3855 fax; marc@energysmiths.comIntegrated Design Consulting ServicesMarc Rosenbaum, P.E.This is a brief description of areas in which I might contribute to a design process concerned with sustainability.

My integrated consulting practice focuses on environmentally sound buildings, creating projects that are safe and healthy, comfortable, durable, and resource efficient. Good environmental design starts with an integrated systems approach.

Areas in which his expertise may be helpful include:

• helping organizations build a united vision of what it is they want to accomplish• setting environmental goals, objectives, and performance metrics
• assembling a architect/engineering/construction team capable of achieving the agreed-upon goals and metrics
• helping to create a design/construction process to achieve the environmental goals
• identifying and managing risk in new approaches and technologies
• user-friendly design• siting for solar utilization and other sustainable systems
• reducing site impact and utilizing site resources
• building envelope detailing for durability and airtightness
• energy efficient construction strategies, insulation choices, types and levels
• healthful materials• resource efficient materials (local, recycled content, low embodied energy)
• ventilation system strategies and heat recovery
• heating and cooling system strategies
• daylighting and energy efficient lighting
• minimizing electrical demand and mechanical parasitic energy use
• glazing types, quantities, orientation
• computer energy use modeling to optimize energy investments
• passive solar design• solar domestic hot water systems and/or graywater heat recovery
• active and/or hybrid solar space heating
• wood-fired space heat and hot water
• solar greenhouse design
• waste treatment strategies, especially composting toilets and graywater treatment
• root cellars, low energy refrigeration, solar food drying
• water conservation
• multiple user mechanical systems and/or district heating
• cogeneration of heat and electricity
• solar electricity

Careful attention to these areas will accomplish the goals of a safe and healthy, comfortable, and durable building, and will greatly improve user satisfaction and resource efficiency over typical construction at modest cost. My efforts here should produce savings, helping you allocate your resources in the best way possible.


you can find more information on marc at:

there are some pictures of his work at:

Keep in mind that his specialty is in the guts. the man thinks of houses like living beings, which is to say beings living together. he works with fragmented products, some of his best ideas involve products that are not yet being produced. working with his extensive knowledge of solar themal and solar electric systems,
he understood many of the problems that the builders and contractors were wondering about.


What is an Energy Audit?

1. Energy Audits/Condition survey

This is the service most often requested by individual homeowners and condo associations. For the single home, our condition survey averages four-to-five hours of on-site investigation. It uses state-of-the-art equipment to performance-test your building. This includes a blower-door to depressurize the house, infrared scans of walls and ceilings, infrared thermometers and a host of other devices. And most importantly, individuals with years of experience to understand how air and energy are traveling through the building.

At the conclusion, you are left with a written checklist called a “condition survey”. This helps you to plan and prioritizes remedies, beginning with the fix that gets you the biggest bang for your buck. The condition survey starts with action items that merit immediate attention followed by items that are not urgent but merit being done when ready.

The Condition Survey is Informed Energy Decisions method of a comprehensive hands-on “energy audit”. Other firms may offer energy audits limited to a review of the financial record of utility bills or may base their assessment on an instrument-free walk-through. “Energy ratings” entail a computer-based extensive compilation of data.

An energy audit entails:

A) Using a puffer to follow the draft by open ductwork
B) The low-E detector checks whether a modern window is genuinely low E
C) Infrared scanner used to read the variations of hot and cold in the walls
D) Condition Survey checklist prepared
E) Blower door pulls air out of the house
F) The infrared thermometer reads surface temperatures
G) In protective gear for investigating the attic, checking the whole house fan.
H) Checking the specifications of the boiler

What is ASTM?

ASTM International is one of the largest voluntary standards development organizations in the world-a trusted source for technical standards for materials, products, systems, and services. Known for their high technical quality and market relevancy, ASTM International standards have an important role in the information infrastructure that guides design, manufacturing and trade in the global economy.

ASTM International, originally known as the American Society for Testing and Materials (ASTM), was formed over a century ago, when a forward-thinking group of engineers and scientists got together to address frequent rail breaks in the burgeoning railroad industry. Their work led to standardization on the steel used in rail construction, ultimately improving railroad safety for the public. As the century progressed and new industrial, governmental and environmental developments created new standardization requirements, ASTM answered the call with consensus standards that have made products and services safer, better and more cost-effective. The proud tradition and forward vision that started in 1898 is still the hallmark of ASTM International.

Today, ASTM continues to play a leadership role in addressing the standardization needs of the global marketplace. Known for its best in class practices for standards development and delivery, ASTM is at the forefront in the use of innovative technology to help its members do standards development work, while also increasing the accessibility of ASTM International standards to the world.

ASTM continues to be the standards forum of choice of a diverse range of industries that come together under the ASTM umbrella to solve standardization challenges. In recent years, stakeholders involved in issues ranging from safety in recreational aviation, to fiber optic cable installations in underground utilities, to homeland security, have come together under ASTM to set consensus standards for their industries.

Standards developed at ASTM are the work of over 30,000 ASTM members. These technical experts represent producers, users, consumers, government and academia from over 100 countries. Participation in ASTM International is open to all with a material interest, anywhere in the world.

Convection, Conduction and Radiation

Convection is the transfer of heat by currents within a fluid. Most fluids are liquids, gasses, and plasmas. It may arise from temperature differences either within the fluid or between the fluid and its boundary, which would affect density. Other sources of density variations, such as variable salinity, or from the application of an external motive force are also often causes. It is one of the three primary mechanisms of heat transfer, the others being conduction and radiation.

Heat conduction is the transmission of heat across matter. Heat transfer is always directed from a higher to a lower temperature. Densersubstances are usually better conductors; metals are excellent conductors.
The law of heat conduction, also known as Fourier's law, states that the time rate of heat flow Q through a slab (or a portion of a perfectly insulated wire, as shown in the figure) is proportionalm to the gradient of temperature difference:

A is the transversal surface area, Δx is the thickness of the body of matter through which the heat is passing, k is a conductivity constant dependent on the nature of the material and its temperature, and ΔT is the temperature difference through which the heat is being transferred. This law forms the basis for the derivation of the heat equation. R-value is the unit for heat resistance, the reciprocal of the conductance. Ohm's law is the electrical analogue of Fourier's law.

Thermal radiation is electromagnetic radiation from the surface of an object which is due to the object's temperature. Heat from a common household radiator is an example of thermal radiation, as is the light emitted by a glowing incandescent light bulb. The thermal radiation is generated when heat from the movement of charged particles within atoms is converted to electromagnetic radiation. For temperatures below "red-hot" (e.g. a household radiator as mentioned above), this radiation is in the infrared freqencies (and thus can be "seen" only with the help of a heat sensor), while for incandescent bodies hotter than "red-hot", as for the common light bulb mentioned above (the filament grows hotter than red-hot), the thermal radiation is visible to the naked eye. At much higher temperatures, such as those on the surface of the Sun, bodies emit radiation again outside of the visible spectrum, this time ultraviolet radiation.

friends, love and heat

What is a Passive House?

A passive house is a building in which a comfortable interior climate can be maintained without active heating and cooling systems (Adamson 1987 and Feist 1988). The house heats and cools itself, hence "passive".

For European passive construction, prerequisite to this capability is an annual heating requirement that is less than 15 kWh/(m²a) (4755 Btu/ft²/yr), not to be attained at the cost of an increase in use of energy for other purposes (e.g., electricity). Furthermore, the combined primary energy consumption of living area of a European passive house may not exceed 120 kWh/(m²a) (38039 Btu/ft²/yr) for heat, hot water and household electricity.

With this as a starting point, additional energy requirements may be completely covered using renewable energy sources.

This means that the combined energy consumption of a passive house is less than the average new European home requires for household electricity and hot water alone. The combined end energy consumed by a passive house is therefore less than a quarter of the energy consumed by the average new construction that complies with applicable national energy regulations.

A passive house is cost-effective when the combined capitalized costs (construction, including design and installed equipment, plus operating costs for 30 years) do not exceed those of an average new home.
Following are the basic features that distinguish passive house construction:

Compact form and good insulation:

All components of the exterior shell of the house are insulated to achieve a U-factor that does not exceed 0.15 W/(m²K) (0.026 Btu/h/ft²/°F).

Southern orientation and shade considerations:

Passive use of solar energy is a significant factor in passive house design.
Energy-efficient window glazing and frames:
Windows (glazing and frames, combined) should have U-factors not exceeding 0.80 W/(m²K) (0.14 Btu/h/ft²/°F), with solar heat-gain coefficients around 50%.

Building envelope air-tightness:

Air leakage through unsealed joints must be less than 0.6 times the house volume per hour.

Passive preheating of fresh air:

Fresh air may be brought into the house through underground ducts that exchange heat with the soil. This preheats fresh air to a temperature above 5°C (41°F), even on cold winter days.
Highly efficient heat recovery from exhaust air using an air-to-air heat exchanger:
Most of the perceptible heat in the exhaust air is transferred to the incoming fresh air (heat recovery rate over 80%).

Hot water supply using regenerative energy sources:

Solar collectors or heat pumps provide energy for hot water.

Energy-saving household appliances:

Low energy refrigerators, stoves, freezers, lamps, washers, dryers, etc. are indispensable in a passive house.


A cohousing community is a kind of intentional community composed of private homes with full kitchens, supplemented by extensive common facilities. A cohousing community is planned, owned and managed by the residents, groups of people who want more interaction with their neighbours. Common facilities vary but usually include a large kitchen and dining room where residents can take turns cooking for the community. Other facilities may include a laundry, pool, child care facilities, offices, internet access, game room, TV room, tool room or a gym. Through spatial design and shared social and management activities, cohousing facilitates intergenerational interaction among neighbours, for the social and practical benefits. There are also economic and environmental benefits to sharing resources, space and items.

Origins of cohousing

The modern theory of cohousing originated in Denmark in the 1960s among groups of families who were dissatisfied with existing housing and communities that they felt did not meet their needs. Bodil Graae published "Children Should Have One Hundred Parents," spurring a group of 50 families to organize around a community project in 1967. Another key organizer was Jan Gudmand Høyer who drew inspiration from his architectural studies at Harvard and interaction with experimental U.S. communities of the era. He published "The Missing Link between Utopia and the Dated One-Family House" paper in 1968, converging a second group.

The Danish term 'bofællskaber' was introduced to North America as 'cohousing' by two American architects, Kathryn McCamant and Charles Durrett, who visited several cohousing communities and wrote a book about it, Cohousing: A Contemporary Approach to Housing Ourselves. The book resonated with some existing and forming communities, such as Sharingwood in Washington state and N Street in California who embraced the cohousing concept as a crystallization of what they were already about.

Growth of Cohousing

Hundreds of cohousing communities exist in Denmark and other countries in northern Europe. There are over 80 operating communities in the United States with about 100 others in the planning phases. In Canada, there are 7 completed communities, and approximately 15 in the planning/construction process. There are also communities in Australia, the UK and other parts of the world.


Because each cohousing community is planned in its context, a key feature of this model is its flexibility to the needs and values of its residents and the characteristics of the site. Cohousing can be urban, suburban or rural. The physical form is typically compact but varies from low-rise apartments to townhouses to clustered detached houses. They tend to keep cars to the periphery which promotes walking through the community and interacting with neighbors as well as increasing safety for children at play within the community. Shared green space is another characteristic, whether for gardening, play, or places to gather. When more land is available than is needed for the physical structures, the structures are usually clustered closely together, leaving as much of the land as possible "open" for shared use. This aspect of cohousing directly addresses the growing problem of suburban sprawl.

In addition to "from-scratch" new-built communities (including those physically retrofitting/re-using existing structures), there are also "retrofit" (aka "organic") communities in which neighbors create "intentional neighborhoods" by buying adjacent properties and removing fences. Often, they create common amenities such as Common Houses after the fact, while living there. N Street Cohousing in Davis, CA, is the canonical example of this type; it came together before the term Cohousing was popularized here.

Cohousing differs from some types of intentional communities in that the residents do not have a shared economy or a common set of beliefs or religion, but instead invest in social capital. A non-hierarchical structure employing a consensus decision-making model is common in managing cohousing. Individuals do take on leadership roles, such as being responsible for coordinating a garden or facilitating a meeting.

Ownership form

Cohousing communities in the U.S. typically rely on one of three existing legal forms of real estate ownership: individually titled houses with common areas owned by a homeowner association, condominiums or a housing co-operative. Condo ownership is most common because it fits financial institutions' and cities' models for multi-unit owner-occupied housing development. U.S. Banks lend more readily on single-family homes and condominiums than housing cooperatives.

Cohousing differs from standard condominium development and master-planned subdivisions because the development is designed by, or with considerable input from, its future residents. The design process invariably emphasizes consciously fostering social relationships among its residents. Common facilities are based on the actual needs of the residents, rather than on what the developer thinks will help sell units. Turnover in cohousing developments is typically very low, and there is usually a waiting list for units to become available.

Thoughts on Sustainable Landscaping

The information below is from a Floridian company, Xeriscape, but these principals can be applied in varied climates:

Xeriscape principles were created by Denver Water in 1982 in response to local drought conditions. Although Xeriscape principles were originally established to promote water conservation, they apply to all aspects of environmentally responsible landscape management.

Along with other areas of the country where water conservation is a serious issue, these principals were quickly adopted for Florida gardening. The increasing population, and its taxation on the water supply, has demanded the promotion of these Xeriscape principles by the Water Management Districts. In addition, the University of Florida Cooperative Extension Service promotes these principles, along with a few additional ones, in their Florida Yards & Neighborhoods program. "Florida Friendly Landscaping" also encourages attracting wildlife, protecting waterfronts, reducing storm water runoff, composting yard wastes, and responsible pest control.

Xeriscape design criterion, in addition to being environmentally friendly, offers a vast assortment of diverse choices for landscape design. In Florida, considerations for plant selection include the water and nutritional needs of the plant without sacrificing the beauty associated with a tropical climate. Plant selection also takes into consideration the desire to attract butterflies, birds and other wildlife. Zones are established that require varying degrees of care, and native plants along with exotic tropicals are carefully placed in the landscape to create a visual impact while keeping maintenance to a minimum.

Turf is also selected for minimum maintenance and kept for high use areas. Conventional landscapes often include vast expanses of lawn that require heavy watering and regular applications of chemical fertilizers, herbicides, and pesticides. Rather than maintaining the sterile uniformity of the American lawn, a variety of grasses and flowering ground covers offer a creative alternative. For those areas where lawn is the best choice, least-toxic sustainable turf care practices must be established.

Planning and Design:

Careful design is crucial to the success of a Xeriscape landscape.
Group plants with similar water requirements.
Increase shade areas to decrease the water needs of plants.
Preserve areas of native vegetation.

Soil Analysis:

Florida soils are mostly sand with very little ability to absorb or hold water. Adding organic matter to the soil improves its water retention. However, due to Florida's high humidity and temperatures, organic matter breaks down quickly. Planting native or adapted plants in the right soil may eliminate the need for soil improvements.

Plant Selection:

Putting the right plant in the right spot is the key to a successful Xeriscape. Select native plants and those adapted to the wet and dry extremes of the Florida climate. Group together plants that require frequent irrigation and keep these groupings to a minimum.

Use Turf Wisely.

Grass tends to use more water and require more maintenace that any other part of the landscape. Therefore, grass should be limited to areas used for recreation and leisure as much as possible. Consider alternatives to grass such as attractive ground covers, decks, patios, and walkways made of permeable materials.

Irrigate Efficiently:

Grouping plants according to their water needs maximizes irrigation efficiency. Select correct irrigation heads for the type of plants being watered. Inspect your system weekly.


Reduce irrigation during the rainy summer and dormant winter.
Use rain gauges and a rain shut-off device to avoid over-watering.
Irrigate during early morning hours when evaporation in minimal.


Use natural mulches for walkways as well as within the planting beds. Mulches reduce watering needs, weeds, erosion, etc.
Practice proper maintenance:


Over-water or over-fertilize. Over-watering increases water costs, disease, and insect problems. Over-fertilizing promotes fast but weak growth and increases water consumption.


Raise mower blades for a higher cut, encouraging grass roots to grow deeper. Prune plants regularly- this prevents overgrowth, encourages healthy growth and keeps water needs to a minimum.

For a sustainable landscape to be established soil health is the next consideration.

Purpose and context shape the design world.

Purpose. The theory of architectural design work is a semantic theory and not a scientific theory. Such a theory has to do with experienced order and meaning; direction; and purpose; assessment and evaluation - all non-scientific terms. Such a theory cannot satisfy those who seek an architectural theory framed along scientific lines.

...many problems of architectural theory stem from a search for meaning and intention in design over and above the meeting of immediate human shelter needs. Architects as a group are prone to philosophies on the nature of man in society; and a man's relationship to his built environment and on the nature of his perception of the world in which he lives. They are forced by the nature of their task to do this in the attempt to match social needs with an appropriate personal vision in order to make a design.

...the environment of human beings is multi-dimensional. ....raw nature ...society, an economy. a civilisation and a culture. If therefore we are to create an intelligible order in our comprehension of universal space ...within our technological age, civilisation and cultural space. A humanising architecture will be of necessity be devised by reference to all these dimensions of human environment. Following this line of thought then architecture as an activity is seen to be the art of bringing order to our spatial environment - in all its dimension.

...For architecture represents a "world". We know that man experiences his environment along two channels - through the immediate sense reactions of his body and through the eyes (or spectacles) of his culture. Architecture concretised both experiences into one totality. As this it is more total activity than either the pure sciences or the fine arts. The coherence of a work of architecture stems not from the objective organisation of clear description, as does the work of science, nor solely for the effect of presentation and symbolisation as do the fine arts; but from the simultaneous organisation and revelation of the character of an enclosed and structured place in physical, social and cultural space. In a work of architecture man/time/place/activity/materials/technology/science/beliefs are resolved and dissolved into plastic organisation, form and image.

...Architecture is best understood as an association of intentions resulting in a work.... (some intentions) permeate the designer's thinking either consciously or unconsciously or unconsciously and relate to ideas of the nature of reality, nature of the physical world and man's relation to it.

...Purpose and context thus shape the design world.

(Oakley, D.The phenomenon of architecture: in cultures of change, Permagon, Oxford 1970)

Tuesday, May 16, 2006

Solar Energy International

Some energy "facts"

Energy Consumption


Though accounting for only 5 percent of the world's population, Americans consume 26 percent of the world's energy. (American Almanac)

In 1997, U.S. residents consumed an average of 12,133 kilowatt-hours of electricity each, almost nine times greater than the average for the rest of the world. (Grist Magazine)

Worldwide, some 2 billion people are currently without electricity. (U.S. Department of Energy)

Total U.S. residential energy consumption is projected to increase 17 percent from 1995 - 2015. (U.S. Energy Information Administration)

World energy consumption is expected to increase 40% to 50% by the year 2010, and the global mix of fuels--renewables (18%), nuclear (4%), and fossil (78%)--is projected to remain substantially the same as today; thus global carbon dioxide emissions would also increase 50% to 60%.

Among industrialized and developing countries, Canada consumes per capita the most energy in the world, the United Sates ranks second, and Italy consumes the least among industrialized countries.

Developing countries use 30% of global energy. Rapid population growth, combined with economic growth, will rapidly increase that percentage in the next 10 years.

The World Bank estimates that investments of $1 trillion will be needed in this decade and upwards of $4 trillion during the next 30 years to meet developing countries' electricity needs alone.

America uses about 15 times more energy per person than does the typical developing country.

Residential appliances, including heating and cooling equipment and water heaters, consume 90% of all energy used in the U.S. residential sector.

The United States spends about $440 billion annually for energy. Energy costs U.S. consumers $200 billion and U.S. manufacturers $100 billion annually.

Global Warming


Worldwide, 1995 was the warmest year since global temperatures were first kept in 1856. This supports the near consensus among climatologists that emissions of carbon dioxide and other gases are causing global warming. (Chivilan and Epstein, Boston Globe)

On average, 16 million tons of carbon dioxide are emitted into the atmosphere every 24 hours by human use worldwide. (U.S. Department of Energy)

Carbon emissions in North America reached 1,760 million metric tons in 1998, a 38 percent increase since 1970. They are expected to grow another 31 percent, to 2,314 million metric tons, by the year 2020. (U.S. Department of Energy)

The United States is the world's largest single emitter of carbon dioxide, accounting for 23 percent of energy-related carbon emissions worldwide. (U.S. Department of Energy)

An average of 23,000 pounds of carbon dioxide are emitted annually in each American home. (U.S. Environmental Protection Agency)

The transportation sector consumed 35% of the nation's energy in 1990; this sector is 97% dependent on petroleum.

Fossil fuels are depleted at a rate that is 100,000 times faster than they are formed.



Approximately 30,000 lives are cut short in the U.S. each year due to pollution from electricity production. (ABT Associates study)

About 81 tons of mercury are emitted into the atmosphere each year as a result of electric power generation. Mercury is the most toxic heavy metal in existence. (U.S. Environmental Protection Agency)

Burning fossil fuels to produce energy releases carbon dioxide and other global-warming-causing gases into the atmosphere. Global warming will increase the incidence of infectious diseases (including equine encephalitis and Lyme disease), death from heat waves, blizzards, and floods, and species loss. (Chivilan and Epstein, Boston Globe, April 10, 1997)



The United States consumes about 17 million barrels of oil per day, of which nearly two-thirds is used for transportation.

The United States imports more than seven million barrels of oil per day.

While the world's population doubled between 1950 and 1996, the number of cars increased tenfold. Automobile congestion in the United States alone accounts for $100 billion in wasted fuel, lost productivity, and rising health costs. Still, analysts project that the world's fleet of cars will double in a mere 25 years. (Worldwatch Institute)

Americans use a billion gallons of motor oil a year, 350 million gallons of which end up polluting the environment. (Department of Energy and Maryland Energy Administration)

A car that gets 20 miles per gallon (mpg) emits approximately 50 tons of global-warming-inducing carbon dioxide over its lifetime, while a 40-mpg car emits only 25 tons. Over the average lifetime of an American car (100,000 miles), a 40-mpg car will also save approximately $3,000 in fuel costs compared to a 20-mpg car. (Natural Resources Defense Council)

The cars and trucks reaching the junkyards this year have higher gasoline mileage, on average, than the new ones rolling off dealers' lots, for the first time on record. (Matt Wald, The New York Times, August 11, 1997)



Only 7.5 percent of total U.S. energy consumption came from renewable sources in 1998. Of that total, 94 percent was from hydropower and biomass (trash and wood incinerators). (U.S. Energy Information Administration)

For the 2 billion people without access to electricity, it would be cheaper to install solar panels than to extend the electrical grid. (The Fund for Renewable Energy Everywhere)

Within 15 years, renewable energy could be generating enough electricity to power 40 million homes and offset 70 days of oil imports.



Providing power for villages in developing countries is a fast-growing market for photovoltaics. The United Nations estimates that more than 2 million villages worldwide are without electric power for water supply, refrigeration, lighting, and other basic needs, and the cost of extending the utility grids is prohibitive, $23,000 to $46,000 per kilometer in 1988.

A one kilowatt PV system* each month:

prevents 150 lbs. of coal from being mined

prevents 300 lbs. of CO2 from entering the atmosphere

keeps 105 gallons of water from being consumed

keeps NO and SO2 from being released into the environment

* in Colorado, or an equivalent system that produces 150 kWh per month



Wind power is the fastest-growing energy source in the world. (Worldwatch Institute)

The wind in North Dakota alone could produce a third of America's electricity. (The Official Earth Day Guide to Planet Repair)

Wind power has the potential to supply a large fraction--probably at least 20%--of U.S. electricity demand at an economical price.

In 1990, California's wind power plants offset the emission of more than 2.5 billion pounds of carbon dioxide, and 15 million pounds of other pollutants that would have otherwise been produced.

Using 100 kWh of wind power each month is equivalent to:

planting ½ acre of trees

not driving 2,400 miles

Solar Thermal


Research shows that an average household with an electric water heater spends about 25% of its home energy costs on heating water.

Solar water heaters offered the largest potential savings, with solar water-heater owners saving as much as 50% to 85% annually on their utility bills over the cost of electric water heating.

You can expect a simple payback of 4 to 8 years on a well-designed and properly installed solar water heater. (Simple payback is the length of time required to recover your investment through reduced or avoided energy costs.)

Solar water heaters do not pollute. By investing in one, you will be avoiding carbon dioxide, nitrogen oxides, sulfur dioxide, and the other air pollution and wastes created when your utility generates power or you burn fuel to heat your household water. When a solar water heater replaces an electric water heater, the electricity displaced over 20 years represents more than 50 tons of avoided carbon dioxide emissions alone.

Alternative Fuels


Using biodiesel in a conventional diesel engine substantially reduces emissions of unburned hydrocarbons, carbon monoxide, sulfates, polycyclic aromatic hydrocarbons, nitrated polycyclic aromatic hydrocarbons, and particulate matter.


can be used at 100% levels or mixed in any proportion with No. 2 diesel or No. 1 diesel.

Contains no nitrogen or aromatics

Typically contains less than 15 ppm sulfur - Does not contribute to sulfur dioxide emissions

Has characteristically low carbon monoxide, particulate, soot and hydrocarbon emissions

Contains 11% oxygen by weight

Has the highest energy content (BTUs) of any alternative fuel and is comparable to No. 1 diesel.

Over 4,000 electric vehicles are operating throughout the United States (with the largest number in California and the western United States).

More than 20,000 flexible-fuel vehicles are in operation.

Over 75,000 natural gas vehicles in U.S. and nearly 1 million worldwide.

Energy Efficiency


By taking appropriate energy-saving measures, by 2010 the United States can have an energy system that reduces costs by $530 per household per year and reduces global warming pollutant emissions to 10 percent below 1990 levels. (Energy Innovations report)

Just by using the "off the shelf" energy-efficient technologies available today, we could cut the cost of heating, cooling, and lighting our homes and workplaces by up to 80%. (U.S. Department of Energy and Maryland Energy Administration)

Replacing one incandescent lightbulb with an energy-saving compact fluorescent bulb means 1,000 pounds less carbon dioxide is emitted to the atmosphere and $67 dollars is saved on energy costs over the bulb's lifetime. (U.S. Environmental Protection Agency and Alliance to Save Energy)

A decrease of only 1% in industrial energy use would save the equivalent of about 55 million barrels of oil per year, worth about $1 billion.

Solar hot water heating

CLOSED-ECL4 ECL-4 Solar Water Heating System - Closed-loop system, one 4x10 collector, for 3 or 4 occupant residence. ($2,599.00)

This closed-loop solar water heating system is designed to give the maximum solar heating benefit for a home occupied by 3 or 4 adults.

* 17: radcoproducts-410php 410P-HP Glazed Flat-Plate Solar Panel, 4x10 feet
* 20: goldline-gl30 Goldline GL-30 differential controller
* 1,6: (two) goldline-sb SB sensor, 10K
* 8: letro-sl2dw3 Letro SL-2DW3 Thermometer
* 2: maidomist-71 MaidOMist Air Vent No.71
* 19: rheem-rhm80hx Rheem Storage Tank, 80gal with internal heat exchanger
* 4: taco-005f2 Taco 005F2 Cartridge Circulator
* 13: tomlinson-c-75 Thomlinson Quadflow bypass "H"valve
* 14: other-s480-075 NIBCO S-480 In-line Check Valve
* 5,16: (two) watts-100xl4 T/P Pressure Relief Valve 212F,150psi
* 9: watts-70a Watts 70A Tempering Valve
* 21: other-p570k-100lm pressure gauge
* 22: amtrol-4un87 Amtrol Expansion Tank
* 23: letro-flow2s Letro LDF357B flowmeter

Includes most of the components of an closed-loop solar water heating system that are necessary to add to an existing residential gas or electric hot water system. Requires 110vac to operate. Installation requires some soldering and wiring. Additional components required: 3/4inch copper piping and fittings, insulation, sensor wire.

We welcome your feedback. Contact us about any difficulty you experience with this shopping service.

In the USA, Order toll-free: 800-589-5560

Telephone 503-635-5560, FAX 503 905-8366
King Solar LLC, West Linn, Oregon, USA Copyright ©1999-2006 King Solar LLC. All Rights Reserved.


There are some really nice products available for heating your hot water and your home. Kaukora Oy is a manufacturer out of Finland.

Monday, May 15, 2006

Solar Hot Water

Solar water heaters, sometimes called solar domestic hot water systems, may be a good investment for you and your family. Solar water heaters are cost competitive in many applications when you account for the total energy costs over the life of the system. Although the initial cost of solar water heaters is higher than that of conventional water heaters, the fuel (sunshine) is free. Plus, they are environmentally friendly. To take advantage of these heaters, you must have an unshaded, south-facing location (a roof, for example) on your property.

Solar Water Heater Basics
Solar water heaters are made up of collectors, storage tanks, and, depending on the system, electric pumps.

There are basically three types of collectors: flatplate, evacuated-tube, and concentrating. A flatplate collector, the most common type, is an insulated, weather-proofed box containing a dark absorber plate under one or more transparent or translucent covers.

Evacuated-tube collectors are made up of rows of parallel, transparent glass tubes. Each tube consists of a glass outer tube and an inner tube, or absorber, covered with a selective coating that absorbs solar energy well but inhibits radiative heat loss. The air is withdrawn ("evacuated") from the space between the tubes to form a vacuum, which eliminates conductive and convective heat loss.

Concentrating collectors for residential applications are usually parabolic troughs that use mirrored surfaces to concentrate the sun's energy on an absorber tube (called a receiver) containing a heat-transfer fluid. For more information on solar collectors, contact EREC.

Most commercially available solar water heaters require a well-insulated storage tank. Many systems use converted electric water heater tanks or plumb the solar storage tank in series with the conventional water heater. In this arrangement, the solar water heater preheats water before it enters the conventional water heater.

Some solar water heaters use pumps to recirculate warm water from storage tanks through collectors and exposed piping. This is generally to protect the pipes from freezing when outside temperatures drop to freezing or below.

Types of Solar Water Heaters
Solar water heaters can be either active or passive. An active system uses an electric pump to circulate the heat-transfer fluid; a passive system has no pump. The amount of hot water a solar water heater produces depends on the type and size of the system, the amount of sun available at the site, proper installation, and the tilt angle and orientation of the collectors.

Solar water heaters are also characterized as open loop (also called "direct") or closed loop (also called "indirect"). An open-loop system circulates household (potable) water through the collector. A closed-loop system uses a heat-transfer fluid (water or diluted antifreeze, for example) to collect heat and a heat exchanger to transfer the heat to household water.

Active Systems use electric pumps, valves, and controllers to circulate water or other heat-transfer fluids through the collectors. They are usually more expensive than passive systems but are also more efficient. Active systems are usually easier to retrofit than passive systems because their storage tanks do not need to be installed above or close to the collectors. But because they use electricity, they will not function in a power outage. Active systems range in price from about $2,000 to $4,000 installed.

Open-Loop Active Systems use pumps to circulate household water through the collectors. This design is efficient and lowers operating costs but is not appropriate if your water is hard or acidic because scale and corrosion quickly disable the system.

These open-loop systems are popular in nonfreezing climates such as Hawaii. They should never be installed in climates that experience freezing temperatures for sustained periods. You can install them in mild but occasionally freezing climates, but you must consider freeze protection.

Recirculation systems
are a specific type of open-loop system that provide freeze protection. They use the system pump to circulate warm water from storage tanks through collectors and exposed piping when temperatures approach freezing. Consider recirculation systems only where mild freezes occur once or twice a year at most. Activating the freeze protection more frequently wastes electricity and stored heat.

Of course, when the power is out, the pump will not work and the system will freeze. To guard against this, a freeze valve can be installed to provide additional protection in the event the pump doesn't operate. In freezing weather, the valve dribbles warmer water through the collector to prevent freezing. Consider recirculation systems only where mild freezes occur once or twice a year at most. Activating the freeze protection more frequently wastes electricity and stored heat.

Closed-Loop Active Systems
These systems pump heat-transfer fluids (usually a glycol-water antifreeze mixture) through collectors. Heat exchangers transfer the heat from the fluid to the household water stored in the tanks.

Double-walled heat exchangers prevent contamination of household water. Some codes require double walls when the heat-transfer fluid is anything other than household water.

Closed-loop glycol systems are popular in areas subject to extended freezing temperatures because they offer good freeze protection. However, glycol antifreeze systems are a bit more expensive to buy and install, and the glycol must be checked each year and changed every 3 to 10 years, depending on glycol quality and system temperatures.

Drainback systems use water as the heat-transfer fluid in the collector loop. A pump circulates the water through the collectors. The water drains by gravity to the storage tank and heat exchanger; there are no valves to fail. When the pumps are off,the collectors are empty, which assures freeze protection and also allows the system to turn off if the water in the storage tank becomes too hot.

in Active Systems
The pumps in solar water heaters have low power requirements, and some companies now include direct current (DC) pumps powered by small solar-electric (photovoltaic, or PV) panels. PV panels convert sunlight into DC electricity. Such systems cost nothing to operate and continue to function during power outages.

Passive systems move household water or a heat-transfer fluid through the system without pumps. Passive systems have no electric components to break. This makes them generally more reliable, easier to maintain, and possibly longer lasting than active systems.

Passive systems can be less expensive than active systems, but they can also be less efficient. Installed costs for passive systems range from about $1,000 to $3,000, depending on whether it is a simple batch heater or a sophisticated thermosiphon system.

Batch Heaters(also known as "bread box" or integral collector storage systems) are simple passive systems consisting of one or more storage tanks placed in an insulated box that has a glazed side facing the sun. Batch heaters are inexpensive and have few components—in other words, less maintenance and fewer failures. A batch heater is mounted on the ground or on the roof (make sure your roof structure is strong enough to support it). Some batch heaters use "selective" surfaces on the tank(s). These surfaces absorb sun well but inhibit radiative loss.

In climates where freezing occurs, batch heaters must either be protected from freezing or drained for the winter. In well-designed systems, the most vulnerable components for freezing are the pipes, if located in uninsulated areas, that lead to the solar water heater. If these pipes are well insulated, the warmth from the tank will prevent freezing. Certified systems clearly state the temperature level that can cause damage. In addition, you can install heat tape (electrical plug-in tape to wrap around the pipes to keep them from freezing), insulate exposed pipes, or both. Remember, heat tape requires electricity, so the combination of freezing weather and a power outage can lead to burst pipes. If you live in an area where freezing is infrequent, you can use plastic pipe that does not crack or burst when it freezes. Keep in mind, though, that some of these pipes can't withstand unlimited freeze/thaw cycles before they crack.

A thermosiphon system relies on warm water rising, a phenomenon known as natural convection, to circulate water through the collectors and to the tank. In this type of installation, the tank must be above the collector. As water in the collector heats, it becomes lighter and rises naturally into the tank above. Meanwhile, cooler water in the tank flows down pipes to the bottom of the collector, causing circulation throughout the system. The storage tank is attached to the top of the collector so that thermosiphoning can occur. These systems are reliable and relatively inexpensive but require careful planning in new construction because the water tanks are heavy. They can be freeze-proofed by circulating an antifreeze solution through a heat exchanger in a closed loop to heat the household water.

Friday, May 05, 2006

Buying a Photovoltaic Solar Electric System

California's Energy Commision put out a consumer's guide to solar electric systems.

Check out the link above. It's a great resource even if you are not resident of California.

Link to NPR Specail Report on Solar

NPR's Jeff Tyler did a special on Going Green.

With energy costs increasing, some analysts point to solar power as a cost cutting solution. But will using sunshine really save you money and add value to your house?

Find out if solar panels might work for your needs. It's a short piece that may answer some basic questions.

Solar Shingles

Solar cells are typically combined into modules that hold about 40 cells; a number of these modules are mounted in PV arrays that can measure up to several meters on a side. These flat-plate PV arrays can be mounted at a fixed angle facing south, or they can be mounted on a tracking device that follows the sun, allowing them to capture the most sunlight over the course of a day. Several connected PV arrays can provide enough power for a household; for large electric utility or industrial applications, hundreds of arrays can be interconnected to form a single, large PV system.

Solar shingles are installed on a rooftop. Thin film solar cells use layers of semiconductor materials only a few micrometers thick. Thin film technology has made it possible for solar cells to now double as rooftop shingles, roof tiles, building facades, or the glazing for skylights or atria. The solar cell version of items such as shingles offer the same protection and durability as ordinary asphalt shingles.

Some solar cells are designed to operate with concentrated sunlight. These cells are built into concentrating collectors that use a lens to focus the sunlight onto the cells. This approach has both advantages and disadvantages compared with flat-plate PV arrays. The main idea is to use very little of the expensive semiconducting PV material while collecting as much sunlight as possible. But because the lenses must be pointed at the sun, the use of concentrating collectors is limited to the sunniest parts of the country. Some concentrating collectors are designed to be mounted on simple tracking devices, but most require sophisticated tracking devices, which further limit their use to electric utilities, industries, and large buildings.

The performance of a solar cell is measured in terms of its efficiency at turning sunlight into electricity. Only sunlight of certain energies will work efficiently to create electricity, and much of it is reflected or absorbed by the material that make up the cell. Because of this, a typical commercial solar cell has an efficiency of 15%-about one-sixth of the sunlight striking the cell generates electricity. Low efficiencies mean that larger arrays are needed, and that means higher cost. Improving solar cell efficiencies while holding down the cost per cell is an important goal of the PV industry, NREL researchers, and other U.S. Department of Energy (DOE) laboratories, and they have made significant progress. The first solar cells, built in the 1950s, had efficiencies of less than 4%.


Types of Panels and Uses

Types of Panels and Their Uses

Solar panels are available in types and sizes for everything from recharging AA batteries to powering large household electrical systems. You can buy small, flexible panels designed for maintaining a fully charged battery (ideal for vehicles that go into storage for months at a time). You can get household power panels ranging up to 120 watt models, and you can add multiple panels to expand the system to any size you need. Of course, the most durable, efficient and highest output panels will be more expensive than the lower-end models, but for large, long-term applications the greater initial outlay is worthwhile in the long run.

Flexible panels are limited to smaller output sizes. They tend to be more expensive per watt of rated output, and less durable in long-term applications. However, they're extremely convenient for intermittent use where the panel may need to be stored and moved around regularly.

Unframed rigid panels also tend to be available primarily in smaller sizes. They're much lighter weight than the more common framed panels, and convenient for portable applications. What these panels lose in convenience as compared to flexible panels, they make up in cost per watt and durability.

Framed rigid panels are the most common type of solar panel for full solar power systems. They are the most durable type of panel, and are generally used in permanent or long term installations for household, RV or marine power systems. Large framed panels can get quite expensive, but with 20-25 year warranties, high durability and low maintenance, they're worth it.

Solar roofing
is one of the newer styles of photovoltaic unit. For a large household system, solar roofing can be found that mimics the appearance of regular roofing shingles or regular metal channel roofing. Probably the most cosmetically pleasing option for a full-house solar system, these products are now becoming available on a widespread basis.

P.V. is More efficient in cold temperatures

photovoltaic panels operate more efficiently in colder temperatures, meaning they produce more power per daylight hour as daylight hours grow shorter. Here are the main considerations for effective use of solar power in northern climates:

Photovoltaic panels will not be much use from November through January, as there simply aren't enough hours of daylight to produce much power (and you'd have to spend a lot of time clearing snow off the panels to make the most of those few hours of light). Plan on having an alternate source of power during these months. Wind generators can be highly effective, if your site has sufficient wind through the winter. Engine generators can also be a good backup source of electricity, as the weather has no effect on their output.

While solar energy is very economical as compared to generator power, it's still a fairly expensive form of electricity. Powering electric heating elements is not an efficient use of your alternative electrical supply. Space heaters, stoves, hot water heaters and clothing dryers should be replaced with non-electric (gas or wood) heat models. (This isn't a bad idea for folks on grid* power either!)

Make sure to place your solar panels in a spot where they won't be shaded by overhanging trees or other obstructions. Even partial shading of a solar panel can significantly reduce its power output.

Choosing the Right P.V. System

The Right System

PV systems are categorized into three types: autonomous, hybrid and grid-connected. The type you choose will depend on your needs, location and budget.

Autonomous systems are completely independent of other power sources. They are usually used to power remote homes, cottages or lodges as well as in applications such as remote monitoring and water pumping. In most cases, an autonomous system will require batteries for storage.

Such systems are particularly useful and cost- effective for summer applications, when access to a site is difficult or costly, or when maintenance needs to be minimized.

Hybrid systems receive a portion of their power from one or more additional sources. In practice, PV modules are often paired with a wind generator or a fuel-fired generator. Such systems usually require batteries for storage.

They are most appropriate when energy demand is high (in the winter or year-round), when power must be available on demand, or if your budget is limited.

Grid-connected systems
allow you to reduce your consumption from the electricity grid and, in some instances, to feed the surplus energy back into the grid. In some cases, your utility may give you credit for the energy returned to the grid. Since power is normally stored in the grid itself, batteries are not necessary unless you want some form of autonomous power during outages.

These systems are used in buildings, homes or cottages already hooked up to the electrical grid.

Friday, April 28, 2006

Indoor Air Treatment

Pure-A-Tech's Patented Air Treatment System Brings Common-Sense Approach to Indoor Air Pollution.

The Environmental Protection Agency has identified that “indoor air quality is the No. 1 environmental health problem today. Indoor air can be up to 100 times more polluted than outdoor air.”

The Pure-A-Tech Air Treatment System (PATS) is the first and only state-of-the-art air-sanitization system that addresses all of the different types of air pollutants that we breathe in our homes every day.

Bad indoor air quality is composed of three distinct elements — particulates, microorganisms and gases. The PATSystem is a patented, three-stage air purifier that is strategically installed on the air-return plenum of the HVAC system sanitizing the air in your entire home. Household air passes through three stages of the PATSystem. Stage 1 collects the particulates such as pollen, dust and pet dander, Stage 2 eliminates the microorganisms such as mold, bacteria and viruses, and finally Stage 3 incorporates a dual-activated carbon that removes gases such as formaldehyde, carbon monoxide, paint and carpet fumes, and it converts ozone into oxygen. Clean air is the best medicine for asthma, allergy and other respiratory problems.

Only the PATSystem continuously provides the cleanest, safest, freshest and healthiest air possible throughout your entire climate-controlled space. It also ensures that your HVAC system will operate more efficiently by keeping it clean. The PATSystem comes with a lifetime warranty.

Thursday, April 27, 2006

Blown Cellulose Insulation

Blowing cellulose insulation into your ceilings and walls is a safe and environmentally-friendly way to make your home more comfortable and more energy-efficient.Fill your Walls & Ceilings, Not our Landfills!We use blown-in cellulose for most of our insulation jobs, (except for crawl spaces, where moisture and the lack of hollow walls won't allow it.) Blown cellulose is less expensive, safer to you as well as the environment and more effective and energy efficient than its leading competitor - fiberglass.

Cellulose fills walls and ceilings and stops air infiltration better!The fibers of cellulose insulation are much finer than fiberglass. When cellulose is blown or dense-packed into your walls and ceilings, it takes on almost liquid-like properties that let it flow into cavities and around obstructions to completely fill walls and seal every crack and seam. No fiberglass or rock wool material duplicates this action. Liquid-applied foam plastics do, but they cost much more than cellulose.

In new construction cellulose insulation can be installed in walls using a spray process or several different dense-pack dry techniques that are also effective at sealing homes against air infiltration.
Cellulose is a naturally recycled product…

Cellulose, which is made from recycled newspapers, is dense-packed between studs on this new construction home. It is blown in through the holes at the top of the picture. Cellulose insulation is made from recycled wood fiber, primarily newspaper. One hundred pounds of cellulose insulation contains 80 to 85 pounds of recycled newsprint. The remainder is made up of Borax and Boric acid, both non-toxic fire retardants. (Borax and Boric Acid are also mold inhibitors!)

Today more and more communities are addressing the challenge of waste disposal through "curbside recycling" and similar conservation programs. These efforts work only if there is demand for recycled products.
The federal government is attempting to create demand through such measures as the Environmental Protection Agency's comprehensive procurement guideline for products containing recovered materials. Cellulose unquestionably meets all requirements for insulation specified by the guideline.

When you choose cellulose insulation you help solve the waste disposal problem and help fight air pollution. This may help your community hold down taxes or refuse disposal charges. It certainly contributes to a cleaner environment.
Paper that is not recycled ends up in landfills, where it may contribute to environmental pollution, or at incinerators where energy is wasted reducing it to ashes, soot, and smoke.

…And a responsible use of resources even if waste paper did not create a disposal problem, most people believe we have an obligation to make maximum use of the resources we consume.

Cellulose insulation does not "save trees," but it makes maximum use of the trees we have already harvested.
Blown Cellulose has the higher savings, lower costs"R-Value" (an expression of heat transfer resistance) is the standard for measuring insulation performance. At R 3.6 to 3.8 per inch, blown-in cellulose insulation is considerably better than fiberglass insulation which has an R-value of about 2.2 to 2.6. But R-value is only one factor in the energy efficiency of a home. Studies of actual buildings regularly show that cellulose-insulated buildings may use 20% to 40% less energy than buildings with fiberglass, even if the R-value of the insulation in the walls and ceilings is identical. One reason for this is the capacity of cellulose to stop air infiltration and heat-zapping convective air currents within your walls and ceilings, which are inherent with most fiberglass insulation.

Cellulose has low embodied energy! Embodied energy is the energy consumed in producing products. Mineral insulation comes from furnaces that gulp natural gas to melt sand, slag, or rock and fiberglass insulation comes from finely spun glass. Foam plastics are petrochemicals and are literally made out of energy!

Cellulose insulation, on the other hand, is made by processing recycled wood fibers -usually newspapers - through electrically-driven mills that consume relatively little energy when they are operating, and which can be shut down completely at the end of the day or even for lunch or coffee breaks.

Fiberglass, rock wool, and plastic insulation may have from 50 to over 200 times more embodied energy than cellulose. By choosing cellulose insulation, you are not only saving money at home but are also decreasing our overall energy demand.

Cellulose makes homes saferMany residential structures contain large amounts of wood. Cellulose insulation is the only wood-based building material that is always treated with fire retardant. We only use cellulose that has been treated with non-toxic Borax and Boric acid and is U.L. listed. This makes cellulose insulation one of the safest materials used in home construction.

If a fire occurs, the dense structure of cellulose and its fire retardants slow its spread through the building by blocking flames and hot gases and restricting the availability of oxygen in insulated walls and ceilings. Scientists at the National Research Council in Canada report that "cellulose in the wall cavity provided an increase in the fire resistance performance of 22% to 55%." Air and fire roar right through fiberglass. This is due to the most flammable tar used on the paper vapor barrier and the low density of fiberglass batts which doesn't block air movement. The NRCC study showed that "the fire resistance of an assembly with glass fiber insulation was slightly lower than that of a non-insulated assembly."

Several fire demonstrations have been conducted in which cellulose-insulated structures have remained virtually intact while uninsulated and mineral-fiber insulated structures burned to the ground.

If Cellulose outperforms fiberglass, why is fiberglass still prevalent in new construction?It is a matter of production vs. performance. Since fiberglass is lower density, it is easier to handle, warehouse and transport. The marketplace still dictates that builders emphasize production, not performance, for the end user (homeowner).
As a homeowner, you can choose performance, more comfort, better fire safety and lower energy bills by choosing Cellulose to "retrofit" and upgrade the insulation in your ceilings, walls and floors.

Cellulose has the highest standards of any insulation materialToday's cellulose insulation is covered by American Society for Testing and Materials Standard Specifications C-739 for loose-fill insulation and C-1149 for spray-applied serf-supporting insulation. Developed and refined over many years through the consensus standard development process of ASTM, the cellulose insulation standards cover several material properties, including: Heat transfer resistance (R-value) Settled (or design) density Critical radiant flux (a measure of surface burning characteristics) Smoldering combustion (an assessment of tire resistance within the insulation layer) Corrosiveness Starch content Odor emission Moisture vapor absorption Fungi resistance Adhesive/cohesive strength (spray-on only)
This industry standard is more comprehensive than the Consumer Products Safety Commission regulation, which has strict requirements for flammability and corrosiveness, but does not address other important characteristics that are not safety-related.